1. Field of the Invention
The present invention relates to a method for forming a scroll member used for a scroll type fluid machine, such as a compressor or an expander.
2. Description of Related Art
Known in a prior art is a scroll compressor having stationary and movable scroll members in a housing. Each of the scroll members is constructed of a base plate and a scroll wall which is integral with respect to the base plate. An orbital movement of the movable scroll member with respect to the stationary scroll member is obtained, while a contact is maintained between the stationary and movable scroll members. Namely, the scroll walls between the movable and stationary scroll member are in a radially contacting condition. Furthermore, the scroll wall of the stationary scroll member is under an axial contacted condition with respect to the facing surface of the base plate of the movable scroll member, while the scroll wall of the movable scroll member is under an axial contacted condition with respect to the facing surface of the base plate of the stationary scroll member.
In order to obtain a desired sealing function, the scroll walls are, at their ends facing the opposite base plates, formed with grooves into which seal rings are placed. Furthermore, the grooves are formed with outer edges which should be bevelled. The machining of the grooves is done by using a rod shaped tool (end mill) with a diameter corresponding to a width of the grooves. Furthermore, after the completion of the grooves, the bevelling of the edges is done by using a tapered tool. Due to the separate machining of the grooves and the bevelling in the prior art, the productivity during the machining is low.